The present invention, in some embodiments thereof, relates to a method for adapting level in a Wake-On-Radio (WOR) system, for example a wake-up threshold level for a radio receiver, and/or a transmit power level of a transmitter in a WOR system.
A Wake-on Radio system typically allows a microcontroller to completely go to sleep, and possibly other sub-units of the system to go to sleep, while a radio receiving unit duty cycles on its own. WOR is typically used to conserve energy use in systems.
WOR systems operate in a variety of environments. Such environments potentially have widely different levels of electromagnetic noise. Some example WOR systems include one or more WOR units located in a house, such as a Home Area Network (HAN) or System, including two or more wireless devices operating at one or more RF channels in a half or full duplex mode. Some of the environments in which WOR units are located are electromagnetically noisy and some of them quieter.
When a WOR system operates in a noisy environment, a radio receiver may receive a false wake-up signal, by detecting a radio signal energy greater than a wake-up threshold, causing a false wake-up of a WOR unit. A false wake-up includes waking up to a signal not intended for the specific WOR unit, and/or waking up to noise instead of a true wake-up signal. Unnecessary wake-ups cause the system various problems, including, for example, depletion of a battery for WOR units, which are often designed to be WOR specifically to save energy and extend battery life.
Background art includes U.S. Pat. No. 5,956,638 to Chang et al., which teaches Radio Ports (RPs) in an unlicensed personal communications system adaptively, autonomously set their interference threshold and/or transmission power levels. This may be done by the RP measuring the signal level on each of the available channels and then setting the interference threshold and/or power level according to these measurements. In a preferred method, the interference threshold is determined by measuring the signal level on each channel, ranking the channels in order of measured signal level, and using these rankings to determine the threshold. The transmission power level may be set with reference to the adaptive interference threshold level. This level is determined by using the system and FCC power limitations and current conditions to provide a satisfactory transmission level.
Additional background art includes:
US Published Patent Application 2010/0054182 of Bachir et al;
U.S. Pat. No. 6,331,834 to Smith;
U.S. Pat. No. 6,201,993 to Kruse et al; and
U.S. Pat. No. 5,956,638 to Chang et al.